Feature: added the two functions for adding and deleting an element.

Author: pokk

adaptiverecyclerview/src/main/java/com/devrapid/adaptiverecyclerview/AdaptiveAdapter.kt

@@ -37,6 +37,7 @@ abstract class AdaptiveAdapter<VT : ViewTypeFactory, M : IVisitable<VT>, VH : Re
             }
         }
     open var diffUtil: AdaptiveDiffUtil<VT, M> = MultiDiffUtil()
+    open var useDiffUtilUpdate = true
 
     protected abstract var typeFactory: VT
     protected abstract var dataList: MutableList<M>
@@ -74,7 +75,11 @@ abstract class AdaptiveAdapter<VT : ViewTypeFactory, M : IVisitable<VT>, VH : Re
     open fun appendList(list: MutableList<M>) {
         val startIndex = dataList.size
         val newList = dataList.toMutableList().apply { addAll(startIndex, list) }
-//        notifyItemRangeChanged(startIndex, list.size)
+        updateList { newList }
+    }
+
+    open fun append(item: M) {
+        val newList = dataList.toMutableList().apply { add(item) }
         updateList { newList }
     }
 
@@ -86,20 +91,24 @@ abstract class AdaptiveAdapter<VT : ViewTypeFactory, M : IVisitable<VT>, VH : Re
         val newList = dataList.toMutableList()
 
         repeat(endIndex - startIndex + 1) { newList.removeAt(startIndex) }
-//        notifyDataSetChanged()
         updateList { newList }
     }
 
+    open fun dropAt(index: Int) = dropList(index, index)
+
     open fun clearList() = dropList(0, dataList.size - 1)
 
     private fun updateList(getNewListBlock: () -> MutableList<M>) {
         val newList = getNewListBlock()
         val res = DiffUtil.calculateDiff(diffUtil.apply {
             oldList = dataList
             this.newList = newList
-        }, true)
+        })
 
         dataList = newList
-        res.dispatchUpdatesTo(this)
+        if (useDiffUtilUpdate)
+            res.dispatchUpdatesTo(this)
+        else
+            notifyDataSetChanged()
     }
 }

sample/src/main/AndroidManifest.xml

@@ -12,10 +12,14 @@
         <activity android:name=".MainActivity">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN"/>
-
                 <category android:name="android.intent.category.LAUNCHER"/>
             </intent-filter>
         </activity>
+        <activity android:name=".DeletableActivity">
+            <!--<intent-filter>-->
+            <!--<action android:name="android.intent.action.MAIN"/>-->
+            <!--<category android:name="android.intent.category.LAUNCHER"/>-->
+            <!--</intent-filter>-->
+        </activity>
     </application>
-
-</manifest>
+</manifest>

sample/src/main/java/com/devrapid/example/DeletableActivity.kt

@@ -0,0 +1,46 @@
+package com.devrapid.example
+
+import android.os.Bundle
+import androidx.appcompat.app.AppCompatActivity
+import androidx.recyclerview.widget.ItemTouchHelper
+import androidx.recyclerview.widget.ItemTouchHelper.DOWN
+import androidx.recyclerview.widget.ItemTouchHelper.LEFT
+import androidx.recyclerview.widget.ItemTouchHelper.RIGHT
+import androidx.recyclerview.widget.ItemTouchHelper.UP
+import androidx.recyclerview.widget.LinearLayoutManager
+import androidx.recyclerview.widget.RecyclerView
+import com.devrapid.example.model.Person
+import kotlinx.android.synthetic.main.activity_deletable.recyclerView
+
+class DeletableActivity : AppCompatActivity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_deletable)
+
+        val itemList: MutableList<IExpandVisitor> = mutableListOf(Person("Google"),
+                                                                  Person("Facebook"),
+                                                                  Person("Apple"),
+                                                                  Person("Amazon"),
+                                                                  Person("HTC"),
+                                                                  Person("Banana"),
+                                                                  Person("Grape"),
+                                                                  Person("Airbnb"),
+                                                                  Person("Jieyi"))
+        val adapter = ExpandAdapter(itemList)
+
+        ItemTouchHelper(object : ItemTouchHelper.SimpleCallback(UP or DOWN, LEFT or RIGHT) {
+            override fun onMove(
+                recyclerView: RecyclerView,
+                viewHolder: RecyclerView.ViewHolder,
+                target: RecyclerView.ViewHolder
+            ) = true
+
+            override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
+                val position = viewHolder.layoutPosition
+                adapter.dropList(position, position)
+            }
+        }).attachToRecyclerView(recyclerView)
+        recyclerView.layoutManager = LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false)
+        recyclerView.adapter = adapter
+    }
+}

sample/src/main/java/com/devrapid/example/ExpandAdapter.kt

@@ -12,7 +12,8 @@ import com.devrapid.example.viewtype.MultiTypeFactory
 class ExpandAdapter(override var dataList: MutableList<IExpandVisitor>):
     AdaptiveAdapter<MultiTypeFactory, IExpandVisitor, AdaptiveViewHolder<MultiTypeFactory, IExpandVisitor>>() {
     override var typeFactory: MultiTypeFactory = MultiTypeFactory()
-    private val originalParentPosition: MutableList<Int> = MutableList(this.dataList.size, { 0 })
+    //    override var useDiffUtilUpdate = false
+    private val originalParentPosition: MutableList<Int> = MutableList(this.dataList.size) { 0 }
 
     class ExpandDiffUtil(private var oldList: MutableList<IExpandVisitor>,
                          private var newList: MutableList<IExpandVisitor>): DiffUtil.Callback() {

sample/src/main/res/layout/activity_deletable.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical">
+
+    <androidx.recyclerview.widget.RecyclerView
+        android:id="@+id/recyclerView"
+        android:layout_width="0dp"
+        android:layout_height="0dp"
+        android:layout_marginBottom="8dp"
+        android:layout_marginEnd="8dp"
+        android:layout_marginStart="8dp"
+        android:layout_marginTop="8dp"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent"/>
+</androidx.constraintlayout.widget.ConstraintLayout>